This is a human flora associated rat model which mimics the microflora of the breast fed human infant. The model involves inoculating germfree infant rats with the faeces of several human breast fed infants and maintaining the rats on a modified infant formula. The rats have been shown to harbour a flora very similar to that of the exclusively breast fed infant, dominated by bifidobacteria and lactobacilli. The caecal and faecal short chain fatty acids and other bacterial metabolic products and activties also mimic the breast fed infant closely. This model gives an excellent opportunity for screening and testing potential food ingredients and probiotics for infant formula and weaning foods. Infant germfree rats are inoculated with human breast fed infant faeces and maintained on a modified infant formula. The effects of test food ingredients can be monitored by changes in the microflora, microbial metabolic activities, markers of gut and microflora maturation, mucosal architecture and immune system. The model has been validated against the faecal constituents of exclusively breast fed human infants. It maintains a flora dominated by bifidobacteria and lactobacilli which is close to that of the breast fed infant and all markers of bacterial metabolic activity are comparable and in the range of the normal breast fed infant.
A model of the colon of the breast fed infant has been developed which will enable testing of potential food ingredients for infant formula and weaning foods. The model is based on a single vessel continuous culture and maintains a flora dominated by lactic acid bacteria, producing mainly acetic and lactic acids. The model has been validated against the contents of the faeces of exclusively breast fed infants. This is this first model of the colon of the exclusively breast fed infant. The model will allow screening and testing of food ingredients and probiotics to reduce the number of expensive and ethically difficult human infant studies. This is an in vitro model of the breast fed infant colon based on the colonic microflora. The model is a continuous culture of infant faecal bacteria using a single vessel and maintained for 2 weeks under anaerobic conditions on a medium based on an adapted infant formula. The dilution rate is 1 volume per day and the cultures are maintained at pH 5.5. No other similar model of the colon of the exclusively breast fed infant is described in the published literature.